This invention relates to control apparatus for aircraft and more particularly to such apparatus for effecting control of thrust magnitude and thrust vector angle for aircraft of the short take-off and vertical landing type known by the acronym STOVL.
Aircraft of this type are known in which the power unit, in addition to providing propulsive thrust for the conventional flight mode is arranged so that the thrust is `vectored` at selectively variable angles to the horizontal to give a short take-off and landing facility or to enable the aircraft to land or take-off substantially vertically, to hover and, in certain circumstances, to give a supplementary in-flight maneuvering capability.
It is also known to provide aircraft with a control system in which various parts of the aerodynamic control surfaces of the aircraft are moved by actuators controlled by means of control signals generated by movement of a controller, which may be a force stick or one pivotally mounted on the aircraft structure for example to one side of the aircraft cockpit. This is a two-axis input device controlling pitch and lateral responses of the aircraft with both similar flight-critical control inputs controlled from a single hand controller.
In achieving a STOVL capability, two flight critical dissimilar inputs are involved, throttle input controlling thrust magnitude, and nozzle input controlling thrust vector angles. In known aircraft having such STOVL capability separate throttle and nozzle levers are employed requiring at least two quite distinct pilot actions. Recent developments in active control systems have permitted the replacement of mechanical control links, previously used on such throttle and nozzle input arrangements, with electrical or optical sensors and signalling.